=10/(x+4)(x-1)-(x+1)(x+4)/(x+4)(x-1)+(x+4)(x-1)/(x+4)(x-1)
=(10-x^2-5x-4+x^2+3x-4)/(x+4)(x-1)
=(-2x+2)/(x+4)(x-1)
=-2(x-1)/(x+4)(x-1)
=-2/(x+4)